The present invention relates to locking apparatus for ball-type trailer hitches and, in particular, to a locking assembly for preventing the unauthorized detachment of the ball and/or mounted trailer from the hitch tongue.
Over the years, a number of locking devices have been developed for boat and utility trailers for separately locking the trailer to the vehicle and for protecting the hitch's ball-receiving socket, when the trailer is detached, to prevent against unauthorized tow-away.
Of the latter types of devices, which appear to be the most common, Applicant is aware of a number of assemblies which may be found upon directing attention to U.S. Pat. Nos. 3,780,546; 4,291,557; 4,542,914; and 4,459,832. Each of these assemblies are of a pseudo-ball construction and mount in locked relation to the trailer coupler's ball socket to prevent access thereto when the trailer is detached.
Of the former devices, a padlock is most commonly mounted through the holes of a spring-loaded lever assembly at the trailer coupler to prevent the release of an associated, wedging yoke which is drawn against/released from the ball upon operating the lever. Upon restraining the lever in its closed position, with the trailer attached to the tow vehicle, the wedging yoke is protected on its underside by the trailer tongue. The padlock, in turn, protects the topside of the coupled assembly.
In this regard, Applicant is also aware of U.S. Pat. No. 3,522,958, which although not disclosing a ball locking assembly, discloses an arrangement for securing the trailer tongue socket to the ball without the necessity of safety chains. It is to be appreciated however that even though the padlocked latch assembly may discourage most would-be thieves, the trailer is still susceptible of theft. That is, the thief need merely unscrew the bolt or nut securing the captured ball to the hitch tongue and reattach the ball to the thief's vehicle. A need, therefore, exists for a lock assembly to separately protect the hitch ball, which may be employed in combination with the trailer coupler lock to prevent the detachment of the entire assembly from the hitch tongue.
Relative to this problem, Applicant is aware of U.S. Pat. No. 4,230,336 which discloses a cam-acting, threaded locking member that mounts within the ball-securing bolt and includes an open-ended guard collar which surrounds the head of the bolt. In combination, the assembly prevents detachment of the hitch ball from the tongue, although requires a specially formed connecting bolt. A need, therefore, still exists for a less-complex, more economically produceable, assembly which readily mounts to and locks the ball to the hitch tongue.